Such a method and device are known from U.S. Pat. No. 3,812,775. In the known method edible products, generally formed from compositions comprising starchy materials and containing natural and/or added sugars, are fried in a two stage frying method. During the first stage the products are fried in oil having a temperature of 110-190° C. to a moisture content of 5-20%, whereas during the second stage the products are fried under a reduced pressure of 50-100 mbar in oil at a temperature not exceeding 100° C. This prevents excessive discoloration of the fried products to occur and provides the required attractive colour to these products.
It is further known from WO-00/30472 to blanch potato strips and the like, where after the strips are fried at atmospheric pressure, cooled and fried in oil at 240-290°F. (115.5-144.4° C.) under vacuum of about 10-20 inches (25.4-50.8 mbar) of mercury.
From EP-1,283,680 a method and device are known for frying products in fat at reduced pressure. Fat is removed from the products by introducing them in a rotating chamber of a centrifuge and by centrifuging them therein at reduced pressure. The products are discharged through a bottom valve of the centrifuge and exposed to the atmosphere through a sluice chamber. An agglomeration of the products is prevented therewith.
It is an object of the present invention to further improve the known frying method, in such a way that time, cost or method savings in combination with enlarged product yield are provided by the associated device, while maintaining essential features of the fried end product, such as texture, colour, taste, aroma, oil/fat content, digestibility, and at the same time reducing thermal reaction products detrimental to humans, such as acrylamid.